1. Field of the Invention
Embodiments of the present invention relate to wind gauges. More particularly, embodiments of the present invention relate to graphical gauges for displaying wind angles and wind speed.
2. Description of the Related Art
Wind gauges are useful in the operation of sailing or wind-powered vessels, because the speed of such a vessel largely depends on the angle it makes with the wind. A wind gauge receives input from a wind angle and speed sensor and displays this data to the user. Conventional wind gauges display a 360-degree view to the user, with angles referenced as 0 degrees to 180 degrees port or starboard from the bow of the vessel.
A close hauled wind gauge differs in that it displays a zoomed-in view of the 360-degree scale, typically magnifying a range of 20 degrees to 60 degrees off the bow and stern. This type of gauge is useful for when the vessel's destination is directly into the wind. As a sailboat cannot move directly into the wind, it must sail in a zigzag pattern, forming a shallow angle with the wind. In order to achieve the maximum possible speed in such a maneuver, it is important that the boat maintains a certain wind angle. Each boat has an ideal wind angle, which varies depending on the design of the sails and the shape of the hull. The close hauled wind gauge provides a more precise view of the wind angle so that the helmsman may sail at or near the ideal wind angle.
The indicator needle of a close hauled wind gauge behaves differently than the indicator needle on a regular wind gauge because only a select range of angles are magnified. So, for example, wind angles 20-60 degrees port and starboard off the bow and 20-60 degrees port and starboard off the stern may be magnified on the close hauled scale, but the remaining angles are compressed or do not have their angles displayed at all.
To achieve the desired magnification, the close hauled wind gauge is often designed to only display 180 degrees against the wind (0-90 degrees port and starboard). Therefore, if a wind angle sensor is pointed at 0 degrees and moved in a complete circle clockwise, the close hauled wind gauge would display the following angles:
AngleBehavior of indicator needle0centered at top of the gauge 0-60moves clockwise to a maximum scale value on the right 60-120holds at the maximum scale value on the right120-180moves counterclockwise to the top of the gauge180-240moves counterclockwise to a maximum scale value on the left240-300holds at the maximum scale value on the left300-360moves clockwise to the top of the gauge
This indicator needle behavior makes it difficult to tell if the vessel is heading upwind or downwind simply by looking at the wind gauge. For example, the indicator needle may be in the same position for 0 degrees as it is for 180 degrees wind angle. Furthermore, the indicator needle may be in the same position for 40 degrees as it is for 140 degrees. Additionally, various vessels may have differing ideal wind angle values, therefore making a close hauled wind gauge with a typical display of 20-60 degrees impractical for use on some vessels.